Such pages become quite complicated. I would rather like to make several separate page definitions that are about the same object, but change their routing such that object is dominating in the URL structure. For example,

Issue Log

The possible clashes would be with defined page names and static content. If there are multiple entity types being used like this, you would also need to specify how to deal with clashes between those. Instead of a different page syntax, which is not very flexible and does not deal with the clashes, we could introduce a routing definition that maps request urls to page calls in whatever way you want. This is similar to the routing DSLs used in many web frameworks.